Symbol complexity and symbol identification with rotated symbols

Previous studies of the identification of rotated symbols have been restricted to either alphanumeric characters or symbols designed to be similar in complexity and type to alphanumerics. These researches have found identification response times to be independent of the magnitude of a symbol's angular displacement from a standard upright position, such findings being typically interpreted as supporting a feature extraction model of identification. In the present experiment complex Japanese characters were used to assess whether such a feature extraction interpretation could be generalized to identifying complex rotated symbols. Identification response times were also found to be constant across all non-standard orientations of the characters, supporting a feature extraction interpretation, but quicker times for standard cases suggested that some qualifications might be necessary.     

Creating and criticizing theory

F. W. Vondracek, R. M. Lerner, and J. E. Schulenberg (Journal of Vocational Behavior, 1983, 23, 179–202) criticize the vocational literature for failing to “follow acceptable scientific procedures for building a theory” and for failing to attend to important methodological and substantive developments. It is argued here that no single acceptable process for creating theory exists and three strategies useful for developing a theory are illustrated: immerse yourself in data, pick a specific set of results to explain, and try to resolve inconsistencies in the literature. Three criteria for evaluating theories and criticisms of them are discussed: comprehensiveness (content value), accuracy (truth value), and clarity (form). The paper by Vondracek et al. is examined from this perspective and is shown to lack the specificity, clarity, and accuracy necessary to be an effective guide to better vocational research or theory.     

Fluid and crystallized intelligence and primacy/recency components of short-term memory

Primacy and recency recall measures, obtained from both free and probed-recall tasks, were included in a battery of tests which also contained markers for fluid intelligence, crystallized intelligence, and cognitive speed factors. Our results confirmed previous findings that for subjects within the normal range of abilities, recency recall from probed-recall tasks is more closely linked to intelligence than is primacy recall. A new finding was also obtained: that primacy recall is correlated more with measures of cognitive speed than is recency recall. These results are discussed in terms of the concept of working memory and its relation to intelligence.     

The complexity continuum in the radex and hierarchical models of intelligence

The hierarchical and radex models of ability organization are shown to be parallel. Both models suggest a complexity continuum along which cognitive performance tasks can be arrayed. In our revised radex model, the complexity continuum from the center to the periphery is shown to correspond to the general-to-specific dimension in factor analyses, or to test correlations with the general factor; complexity is redefined as apparent processing complexity. Examination of the theoretical and empirical bases for this continuum indicates its central importance for theories of intelligence.     

What is educational theory and how to make it?

An analysis is provided detailing the conditions for the appropriate theoretical study of the object of educational science: pedagogy.     

Do medical decision analyses' largest gains grow from the smallest trees?

Some decision analysts recommend reserving their models for careful, complete study of complex problems. Others believe simple problem analyses provide the greatest gains. To clarify these issues, I tested: (1) whether simple published analyses compared to complex ones, produced results as non-intuitive; and (2) whether non-intuitiveness represented analytic gain (or equivalently, intuitive loss). Very limited data also examined (3) the gain from adding model intricacy for a given problem vs. selecting more complex problems for analysis. To assess two non-intuitiveness measures, 75 subjects (33 physicians and 42) non-physicians stated their intuitive preferences in 40 (22 published and 18 unpublished) medical dilemmas. For both physicians and non-physicians, simpler models (those with lees than 30 terminal branches in the decision tree) had about one third the non-intuitiveness of more complex ones. Three tests also supported the premise that analyses outperform intuition, therefore that on average the formers' non-intuitiveness reflects less analytic gain. In addition, for different models of the same problem, tree complexity did not correlate with gain. Thus, simpler trees may not generally gain less because they inadequately describe problems. Instead, simpler analyses may represent simpler problems, with more similar intuitive and formal solutions. If so, these findings may help us avoid some costly but unnecessary simple analyses.     

The time course of extinction-induced aggressive behavior in humans: Evidence for a stage model of extinction

Three experiments examined the effects of extinction on aggressive responding in male college students. In Experiment 1 subjects initially performed on a task where shuttle responding was either continuously or partially reinforced with tokens while either a nonaggressive button-pressing response or an aggressive pad-striking response was concurrently reinforced by escape from a moderately aversive tone. During shuttle acquisition there was clear preference for the escape response of button pressing, but when shuttle responding was extinguished subjects began to respond aggressively by striking the pad to escape. The time course of aggressive escape responses during concurrent shuttle extinction was an inverted U; aggressive responding rose to a peak and then declined. Aggressive responding began earlier in extinction following continuous- as contrasted with partial-reinforcement shuttle training. Experiment 2 showed that similar extinction-induced aggression was precipitated by both moderate and extended continuous-reinforcement shuttle training, with earlier onset after extended reinforcement. Experiment 3 ruled out the possibility that the emergence of the pad-striking response during extinction was simply induced response variation. These data were interpreted within the theoretical framework of P.T.P. Wong's recently advanced stage model of extinction (Animal Learning and Behavior, 1978,6, 82–93).     

Within-compound associations between the context and the conditioned stimulus

Three experiments were conducted to test for the presence of associations between contextual cues and the nominal conditioned stimulus (CS) in fear conditioning. Rats were given tone-footshock pairings and were tested for their fear of the nominal CS, the tone, in a different context. Experiments 1 and 2 demonstrated that rats given nonreinforced exposure to the training context following conditioning were less fearful of the CS. Experiment 3 indicated that additional footshock presentations in the training context following conditioning produced greater fear of the CS. In both procedures postconditioning treatments designed to directly alter only the associative strength of the training context yielded parallel changes in the conditioned response to the CS. These data suggest that within-compound associations are formed between the context and the CS during classical conditioning.     

Lithium-mediated disruptions of latent inhibition: Overshadowing by the unconditioned stimulus in flavor conditioning

In a series of experiments, the ability of a single lithium preexposure to disrupt CS effectiveness was assessed using a latent inhibition procedure. Lithium preexposure administered proximal (90 min) to a saccharin familiarization trial reduced latent inhibition whereas a similar administration more distal (360 min) to flavor familiarization failed to do so. Additional experiments demonstrated that this socalled “US overshadowing” effect was not attributable to sensitization (Experiment 2), excitatory backward conditioning (Experiment 3), or state dependency (Experiment 4). The implications of US overshadowing for proximal US-preexposure effects are discussed.